Bituminous composition



Patented July 7, 1942 llNlTED STATE BITUMINOUS COMPOSITION David R.Wiggam, West Grove, Pa,

Hercules Powder Company, Wilmingt a corporation of Delaware assignor to001, Del,

No Drawing. Application April 0, 19st,

. Serial No. 200,450

10 Claims.

a have found wide commercial use due to their excellent water-proofingproperties. As a class,

however, they all have either one or the other, or

both, of .two rather serious defects. One of these defects is a tendencyto soften and flow at summar atmospheric temperature. The other is atendency to brittleness at normal and lower than normal temperatures.

I have found that ethyl cellulose has the effect of increasing themelting point and greatly ini5 creasing the toughness of the variousbituminous materials,- even when present in relatively smallproportions. Thus, by the addition-oi ethyl cellulose to bituminousmaterial, I can obviate,

to a large extent, their two most serious defects.

The compositions in accordance with this in- 'vention will comprise abituminous material homogeneously admixed with ethyl cellulose. Therelative amounts of the bituminous material and of ethyl -cellulosewhich I may use will depend upon the extent to which it is desired toalter the characteristics of the bituminous ma-= terial. The weight ofethyl cellulose used will, in general, be less than the weight ofbituminous material used and for many purposes the relative proportionof the ethyl cellulose will be much smaller. I

Bituminous materials are usually defined as a class of native orpyrogenous substances containing bituminous or pyrobltuminous, orresembling them in their physical properties. The composition inaccordance with this invention may contain any of these substanceshomogene ously admixed with ethyl cellulose. TIhebitumlnous materialwhich I may use may be, for example, gilsonite, coal tar, pine tar,stearlne pitch,

coal tar pitch, Trinidad asphalt, Mexican crude petroleum asphalt,Mexican crude blown petroleum asphalt, etc.

The ethyl cellulose which I may use may have a wide range ofviscosities, although, in general, I prefer to use a comparatively highviscosity type. I may use, for example, an ethyl cellulose having aviscosity characteristic within the range of about 3-4 seconds to about500 seconds, although, in general, I prefer to use one having aviscosity characteristicwithin the range of about 6-8 seconds to about60-80 seconds. I may utilize an ethyl cellulose having an ethoxy contentwithin the range of about 44% to about 49.5% by weight, and, in general,prefer one having an ethoxy content within the range of about 46% toabout 48% by weight.

The ethyl cellulose and bituminous material ethyl cellulose in thebituminous material, provided the molten bituminous material is asolvent for ethyl cellulose. Bituminous materials which are rich inaromatic hydrocarbons, esters and/or alcohols, when in the moltencondition, are solvents for ethyl cellulose. Examples of such bituminousmaterials are gilsonite, coal tar, pine tar, stearine pitch, etc.

- The bituminous materials which are rich in straight chainhydrocarbons, when in the molten condition, are not solvents for ethylcellulose. Ethyl cellulose may, however, be dissolved in such bituminousmaterials, when in the molten condition, by the aid of a suitable flux.Bituminous materials which require the aid of a flux to dissolve ethylcellulose are, for example, coal tar pitch, Trinidad asphalt, Mexicancrude petroleum asphalt; etc. The flux used to dissolve ethyl cellulosein normally non-solvent bituminous materials may be any substantiallynon-volatile material which, in the molten condition, is a solvent -forethyl cellulose, such as, for example, rosin,

modified and unmodified non-heat convertible phenol-formaldehyde resins,the higher fatty acids, as, stearic acid, linseed oil fatty acids, cas-'tor oil fatty acids, etc., waxes, as, montan wax, beeswax, Japan wax,etc., the bituminous materials rich in aromatic hydrocarbons, estersand/or alcohols mentioned *hereinbefore, etc; The amount of the solventflux used will depend upon its solvent activity for ethyl cellulose, butwill ordinarily be used in amount within the range of about 50 to about75%, by weight, of the mixture of the solvent and non-solvent materialssolvent types of bituminous materials.

' The compositions in accordance with this invention may contain variousmodifying agents such as, plasticizers, waxes, resins and fillers inaddition to ethyl cellulose and the bituminous material. Theplasticizers which are suitable for use in the compositionin accordancewith this invention are, for example, triphenyl phosphate, dibutylphthalate, chlorinated. diphenyl, castor oil, hydrogenated ethylabietate, hydrogenated methyl abietate, ethyl abietate, methylabletate,etc. Suitable waxes are, for example, montan wax, beeswax, Japan wax,Carnauba wax, etc. Suitable resins are, for example, modified andunmodified non-heat convertible phenol-formaldehyde type resins, Boearesin, cumarone-indene may be homogeneously admixed by dissolving the cosynthetic resins, rosin, etc. Fillers which may be used are, forexample, wood flour, ground cotton linters, clays, zinc oxide,comproteins, etc. The particular modifying ingredients added and theiramount will depend upon the purpose for which the completed plastic isvto be used.

The compositions in accordance with this invention, details for theirpreparation and their properties in comparison with the unmodifiedbituminous materials, are illustrated by the 101-- v lowing tables:

Turn I Heat-fusion mixtures of ethyl cellulose and gilsontte Example No.

Glknnlfn Ethyl cellulose med. vhcoslty Fused at-. Mutual solubilitySoftening pt. drop moth geltlng pt. drop method..."

Tsar: II

Heat-fusion mixtures of ethyl cellulose and coal tar Example N o.

Coal tar- 100 900 75 66% 50 Ethyl cellulose mod. viscosity 0 10 5g Fusednt 170 0 170 C 170 0 200 0. Mutual solubility Good Good Good Good.Softening t. drop method (Barrett's) 675 C 950 0 119 C 143.0 C. Meltingp drop method (Barrett's) 1 8 C 132.0 C... 171.0 C. Gusts Too soitExcellent Excellent... Excellent.

Tsar: DI

Heat-fusion mixture; of ethyl cellulose and stearine pitch Example No.

Btearino fiitch Ethyl oe nlooe high viscosity Fused at Mutual solubilityBoitening pt. drop metbod-..- 0 C Melting t. drop method Costa.

Tau IV Heat-fusion mixture: of ethyl cellulose, coal tar pitch and aflu:

- Exnmple No.

Cool tar pitch (Barrett's Roofing itch) 98 98 97 97 V l' 0 2 2 8 3 Ethylcellulose low viscoal 0 0 1 3 3 Softening pt. drop method" 0. 63.0 67.070.0 920 78.0 Melting point drop method.--0-. 71. Q 71. 0 74. 6 98. 0 8L0 A gasoline-insoluble resin obtained tom pine wood.

Tut: V

Heat-fusion mixtures of ethyl cellulose and coal tar- Example No.

Ethyl cellulose low 40% by wt.. 40% by wt.- 40% by wt viscosity- Ewe.Rosin mod ed male- 6% by wt.-. 15% by wt-- 30% by wt ate (Amberol 800).Refined coal tar 54% by wt 45% by wt 30% by wt Blending temperature 210C 210 C. '210 C. Time, required to 2bours 2 hours 1 hr. 50 min Goo GooGood. ood d Good. Fair viscous. Fair viscous. Fair viscous lack Black.Tack iree Tack freem. Tack free 132 C ISO-134 C-.- lilo-134 0 Impactstrength 2.59. lb.... 2.34ft.lb 08nft.lb

(ch py)- Cold flow 0.085 mm. 0.26 mm"... 0.09 mm Piund hardness 34.0...40.0 138.0.

Examples of compositions in accordance with this invention suitable'forspecific purposes are illustrated by the following:

EXAMPLE 22 Insulating composition Sealing composition for blasting capsEthyl cellulose (medium viscosity) parts" 5.0 Rosin (colo'r grade of N)do 34.4 Coal tar (Barrett's melting point) do 129.6 Crude montan wax do8.0 Hydrogenated methyl abietatedo 16.0 Saybolt furol viscosity at 150 Csecs 43 Melting point, ring and ball method Penetration at25 62,100 g.,sec

' EXAMPLE 25 Heat-fusion mixtures of ethyl cellulose, Trinidad asphaltand a flux The following homogeneous mixture was prepared using a flux:

' Per cent by weight Ethyl cellulose (low viscosity type) 10 Wood rosin(color grade of N) 4o Trinidad asphalt 4c The ethyl cellulose wasdissolved in melted rosin at a temperature of 175 C. When completelydissolved, the asphalt was addedto the hot molten mixture and blended inat 175 C. .When cast and cooled, the final mixture was found to beHeat-fusion mixtures of ethyl cellulose, Mexican crude petroleum asphaltand a flux The following mixture was prepared by the procedure describedin Example 25:

, Per cent by weight Ethyl cellulose (lowviscosity type) 10 Rosin- 50Mexican crude partially blown petroleum asphalt (180 F. softening point)40 when cast and cooled this mixture was found to be homogeneous andfree of lumps-or granulesof gelled or precipitated ethyl cellulose.

The details and examples given herein are by way of illustration and notby way of limitation of the invention as broadly described and claimed.

What I claim ancldesire to, protect by Letters Patent is:

1. A composition of matter comprising in homogeneous admixture abituminous material selected from the group consisting of coal tar, pinetar, gilsonite, and stearine pitch; and ethyl cellulose, the compositionconsisting of non-volatile substances and having a higher softeningpoint and greater toughness than the bituminous material.

2. A composition of matter comprising in homogeneous admixture abituminous material selected from the group consisting of coal tar, pinetar, gilsonite, and stearine pitch; and ethyl cellulose in a quantityless than that of the bituminous material, the composition consisting ofnon-volatile substances and having-a higher softening point and greatertoughness than the bituminous material.

3. A composition of matter comprising coal tar and ethyl cellulose inhomogeneous admixture, the composition consisting of non-volatilesubstances and having a higher softening point and greater toughnessthan the coal tar;

4. A composition of matter comprising pine tar and ethyl cellulose inhomogeneous admixture, the composition consisting of non-volatilesubstances and having a higher softening point and greater toughnessthan the pine tar.

5. A composition of matter comprising stearine pitch and ethyl cellulosein homogeneous admixbituminous material selected from the groupconsisting of coal tar, pine tar, gilsonite, and stearine pitch;' andethyl cellulose in homogeneous admixture therewith -in a quantity lessthan that 3 of the bituminous material, the composition having a highersoftening point and greater toughness than the bituminous material.

cellulose in a quantity less than that of the coal tar, the compositionbeing. characterized by stability and by a higher softening point and ,agreater toughness than the coal tar.

9. A composition of matter consisting in homogeneous admixture oi pinetar and ethyl cellulose in a quantity less than that of the pine tar,the composition being characterized by stability and by a highersoftening point and a 5 greater toughness than the Pine tar.

10. A composition or matter consisting in homogeneous admixture ofstearine pitch and ethyl cellulose in a quantity less than that of thestearine pitch, the composition being characterized by stability and bya higher softening point and a greater toughness than the stearinepitch.

' -DAV]I R. WIGGAM.

